Guide Book, Volum 2

abundant accessory constituents albite alkali syenites alteration alumina amphibolite analysis asbestos Bancroft bands batholith beds biotite Black Lake border Broughton calcite cent character chromite coarse colour composed contains corundum Craigmont crystalline limestone crystals deposits diabase diorite distinctly foliated district dungannonite dykes exposures feet feldspar foliation gabbro Geol geological Glamorgan gneiss gneissic grains granite granite-gneiss Grenville series grey Haliburton hastingsite hornblende igneous inclusions intrusion invading rock iron K₂O Laurentian Lawrence lime limestone magma magnetite mass Maxwell's Crossing metamorphism microcline microscope miles mined mineral muscovite nepheline rocks nepheline syenite occur Ontario Ordovician original orthoclase pegmatite peridotite places plagioclase portion Pre-Cambrian present protaxis pyroxene pyroxenite quantitative classification quartz railway represent road rock types scapolite schlieren sedimentary sediments seen serpentine showing silicates SiO2 small amount specimen strata structure syenite pegmatite Thetford thin sections Township of Monmouth usually variety veins vicinity